CONTENTS

 1     Scope 
 2     References 
 3     Definitions  
 4     Abbreviations   
 5     Description
 6     Operational requirements 
        6.1     Provision/withdrawal          
        6.2     Requirements on the originating network side          
        6.3     Requirements on the destination network side         
 7     Coding requirements        
 8     State definitions
        8.1     User states
        8.2     Network states      
 9     Signalling procedures at the coincident S and T reference point     
        9.1     Procedures at the served user's interface    
                  9.1.1     Activation 
                  9.1.2     Deactivation         
                  9.1.3     General interrogation         
                  9.1.4     Particular interrogation      
                  9.1.5     Recall indication    
                  9.1.6     CCNR call request           
                  9.1.7     CCNR call establishment  
                  9.1.8     Network initiated deactivation procedures 
                  9.1.9     B free but A busy procedure         
                  9.1.10     User A monitoring procedure      
                  9.1.11     Call information retention
                  9.1.12     Basic call information and compatibility checking 
        9.2     Procedures at the remote user's interface    
                  9.2.1     Acceptance of a CCNR request   
                  9.2.2     CCNR queue processing  
                  9.2.3     Determination of user B free          
                  9.2.4     CCNR call           
10     Procedures for interworking with private ISDNs  
       10.1     Procedures for the originating T reference point     
                  10.1.1     CCNR available indication          
                  10.1.2     CCNR supplementary service request     
                  10.1.3     Remote user free indication         
                  10.1.4     Suspend request 
                  10.1.5     Resume request  
                  10.1.6     CCNR call establishment
                  10.1.7     Deactivation       
       10.2     Procedures for the destination T reference point    
                  10.2.1     CCNR available indication          
                  10.2.2     CCNR supplementary service request     
                  10.2.3     Remote user free indication         
                  10.2.4     Suspend request 
                  10.2.5     Resume request  
                  10.2.6     CCNR call establishment
                  10.2.7     Deactivation       
11     Interactions with other networks  
       11.1     Interaction with non-ISDNs          
12     Interaction with other supplementary services      
       12.1     Call Waiting (CW)
       12.2     Explicit Call Transfer (ECT)          
       12.3     Connected Line Identification Presentation (COLP)           
       12.4     Connected Line Identification Restriction (COLR) 
       12.5     Calling Line Identification Presentation (CLIP)       
                  12.5.1     Coding requirements       
                  12.5.2     Procedures at the coincident S and T reference point       
                  12.5.3     Procedures for interworking with private ISDNs  
       12.6     Calling Line Identification Restriction (CLIR)         
                  12.6.1     Coding requirements       
                  12.6.2     Procedures at the coincident S and T reference point       
                  12.6.3     Procedures for interworking with private ISDNs  
       12.7     Closed User Group (CUG)           
       12.8     Conference Calling (CONF)         
       12.9     Direct-Dialling-In (DDI)    
      12.10     Call diversion (call forwarding) services    
                  12.10.1     Call Forwarding Busy (CFB)    
                  12.10.2     Call Forwarding No Reply (CFNR)      
                  12.10.3     Call Forwarding Unconditional (CFU)   
                  12.10.4     Call Deflection (CD)     
      12.11     Line Hunting (LH)
      12.12     Three-Party Service (3PTY)        
      12.13     User-to-User Signalling (UUS)    
      12.14     Multiple Subscriber Number (MSN)        
                  12.14.1     Coding requirements     
                  12.14.2     Signalling procedures at the coincident S and T reference point  
                  12.14.3     Procedures for the remote network       
      12.15     Call Hold (HOLD)          
      12.16     Advice of Charge (AOC)
      12.17     Sub-addressing (SUB)     
      12.18     Terminal Portability (TP)  
      12.19     Completion of Calls to Busy Subscriber (CCBS)  
                  12.19.1     Coding requirements     
                  12.19.2     Signalling procedures at the coincident S and T reference point  
      12.20     Malicious Call Identification (MCID)        
      12.21     Reverse Charging (REV) 
      12.22     Multi-Level Precedence and Preemption (MLPP)
      12.23     Support of Private Numbering Plan (SPNP)         
      12.24     International Telecommunication Charge Card (ITCC)     
      12.25     Global Virtual Network Services (GVNS)           
      12.26     Call Completion on No Reply (CCNR)    
13     Parameter values (timers)
14     Dynamic description (SDLs)       
Appendix I – Signalling flows